1. Field of Invention
The present disclosure relates to an active device array substrate with a flexible substrate.
2. Description of Related Art
Electro-phoretic displays (EPDs) were developed in 1970s. Such a first-generation EDP comprises many small charged balls that are white on one side and black on the other side. The balls rotate to show different colors under a varied electric field. Second-generation electronic paper displays were developed in the 1990s. In a second-generation EDP, microcapsules filled with colored oil and charged white particles replace the small charged balls. An external electric field controls the movement of the white particles. The display shows a white color when the white particles move upward (toward the user), while it shows the color of the oil when the white particles move downward (away from the user).
In general, an EPD is formed of an active device array with a glass substrate. Although the EPD owns higher hardness, the heavy weight that is not easy to be portable and the fragment are the problems.
Recently, the industry in the art promotes an EPD formed of active device array with plastic substrate. Since they are flexible in a certain extent, they may replace the traditional paper or the billboards. During the manufacture of the EPDs, the manufacturer needs to fix the active device array substrate on the glass substrate to adapt to the present machines since the active device array substrate is made of plastic. However, the stress may be stored within the active device array substrate and the glass substrate during the heat process since the thermal expansion coefficients of the plastic, the glass, and even the inorganic dielectric layer, such as the gate dielectrics and the passivation, on the active device array substrate exist huge differences. Therefore, it may produce the deformations of the active device array substrate and the glass substrate to occur problems such as slides crashed or weak adhesion of the slides on the machine.